As electronic devices continue to get smaller, while the performance thereof continues to improve, there is an ever growing need for smaller, lighter, and more powerful batteries that demonstrate suitable reliability and longevity.
One possible solution for these batteries is solid-state lithium batteries. Current goals with respect to solid-state lithium batteries include a volumetric energy density greater than 1000 Watt hours per liter (Whr/L). Ideally, the batteries would be able to cycle to 500 cycles with less than 20% volumetric energy density loss at temperatures between 30° C. and 40° C. It is also desirable to keep the batteries, and of the components therein, as thin as possible while maintaining such performance.
Using conventional materials, such as lithium-cobalt oxide, in the cathodes of the batteries typically requires the cathode to be at least 10 micrometers thick for the overall system to have an energy density that greater than 625 Whr/L, let alone higher.
However, current lithium-cobalt oxide electrodes grown on conductive films (e.g. gold) are limited to a thickness of about 4 micrometers. When the thickness is increased to greater than 5 micrometers, the electrodes exhibit decreased utilization at charge rates above C/5. This decreased utilization is due to crystallographic defects, improperly oriented crystal texture, increased electrical resistance, and other mechanisms which impede lithium ion diffusion.